Template manufacturing method and template base member

ABSTRACT

A template manufacturing method includes preparing a structure including a first substrate and a stacked body that is provided on the first substrate, the stacked body including a first lower layer including a first material, a first upper layer provided on the first lower layer including a second material different from the first material, and a first cover layer provided on a first cover region of the first upper layer and including a third material different from the second material. The method further includes forming a first resist layer on a portion of the first cover layer and on a first portion of the first upper layer, and exposing a second portion of the upper layer. The method yet further includes removing the second portion of the first upper layer using the first cover layer and the first resist layer as a mask.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of and priority to Japanese PatentApplication No. 2017-053318, filed Mar. 17, 2017, the entire contents ofwhich are incorporated herein by reference.

FIELD

Embodiments described herein relate generally to a templatemanufacturing method and a template base member.

BACKGROUND

There are pattern forming methods of transferring step-shaped patternsto substrates by imprinting using templates that define the step-shapedpatterns. For example, films provided in semiconductor devices areprocessed using the transferred patterns. It is preferable in someimplementations for the templates to have highly precise shapes.

DESCRIPTION OF THE DRAWINGS

FIG. 1A, FIG. 1B, FIG. 1C, FIG. 1D, FIG. 1E, and FIG. 1F are schematicsectional views showing embodiments of a method of manufacturing atemplate according to a first aspect.

FIG. 2A, FIG. 2B, FIG. 2C, FIG. 2D, FIG. 2E, and FIG. 2F are schematicsectional views showing embodiments of a method of manufacturing thetemplate according to the first aspect.

FIG. 3A, FIG. 3B and FIG. 3C are schematic sectional views showingembodiments of a method of manufacturing the template according to thefirst aspect.

FIG. 4A, FIG. 4B, FIG. 4C, FIG. 4D, FIG. 4E, and FIG. 4F are schematicsectional views showing embodiments of a pattern forming method usingthe template according to the first aspect.

FIG. 5A and FIG. 5B are schematic sectional views showing embodiments ofa template according to the first aspect.

FIG. 6A, FIG. 6B, FIG. 6C, FIG. 6D, FIG. 6E, and FIG. 6F are schematicsectional views showing embodiments of a method of manufacturing atemplate according to a second aspect.

DETAILED DESCRIPTION

Example embodiments described herein provide for a templatemanufacturing method and a template base member capable of improvedprecision.

In some embodiments according to one aspect, a template manufacturingmethod includes preparing a structure including a first substrate and astacked body provided on the first substrate. The stacked body includesa first lower layer including a first material, a first upper layerprovided on the first lower layer and including a second materialdifferent from the first material, and a first cover layer provided on afirst cover region of the first upper layer and including a thirdmaterial different from the second material. The template manufacturingmethod includes forming a first resist layer on a portion of the firstcover layer and at least a portion of a region excluding the first coverregion of the first upper layer. The template manufacturing methodincludes removing a portion of the first upper layer using the firstcover layer and the first resist layer as a mask to expose a portion ofthe first lower layer.

In some embodiments, according to another aspect, a templatemanufacturing method includes preparing or providing a first templatethat includes a plurality of stacked films, each of the plurality ofstacked films including a lower layer including a first material and anupper layer including a second material different from the firstmaterial, and a first surface of the first template including a stepstructure in which one or more a steps are defined by each of theplurality of stacked films. Forming a resin layer to form a secondtemplate includes disposing a resin liquid film between the firsttemplate and a second substrate, and solidifying the resin liquid filmwhile the first surface of the first template is in contact with theresin liquid film to form the resin layer defining a resin layer surfaceshape that corresponds to a shape of the step structure.

In some embodiments, according to another aspect, a template base memberincludes a plurality of first layers comprising a first material, and aplurality of second layers comprising a second material different fromthe first material. The first layer and the second layer are alternatelystacked.

Hereinafter, embodiments of the present disclosure will be describedwith reference to the drawings. The drawings are schematic andconceptual. Relations between thicknesses and widths of portions, ratiosof sizes between the portions, and the like may not necessarily be thesame as the actual relations, ratios, and the like. When the sameportions are illustrated, dimensions and ratios of the portions maydiffer between drawings in some cases.

In the present specification and the drawings, the same referencenumerals are given to the same or similar elements, and repetitivedetailed description thereof will be appropriately omitted.

First Aspect

FIG. 1A through FIG. 1F, FIG. 2A through FIG. 2F, and FIG. 3A throughFIG. 3C are schematic sectional views showing embodiments of a method ofmanufacturing a template according to a first aspect.

As illustrated in FIG. 1A, a structure 10 is prepared or provided. Thestructure 10 includes a first substrate 11 and a stacked body 12. Thestacked body 12 is provided on the first substrate 11.

The stacked body 12 includes a plurality of lower layers (such as afirst lower layer L1, a second lower layer L2, and a third lower layerL3) and a plurality of upper layers (such as a first upper layer U1, asecond upper layer U2, a third upper layer U3, and a fourth upper layerU4). The plurality of lower layers and the plurality of upper layers arealternately arranged. Any number of lower layers and any number of upperlayers can be used.

For example, the first lower layer L1 is located between the first upperlayer U1 and the first substrate 11. The second upper layer U2 islocated between the first lower layer L1 and the first substrate 11. Thesecond lower layer L2 is located between the second upper layer U2 andthe first substrate 11. The third upper layer U3 is located between thesecond lower layer L2 and the first substrate 11. The third lower layerL3 is located between the third upper layer U3 and the first substrate11. The fourth upper layer U4 is located between the third lower layerL3 and the first substrate 11.

The plurality of lower layers including the first lower layer L1, thesecond lower layer L2, and the third lower layer L3 contain a firstmaterial. For example, the first lower layer L1, the second lower layerL2, and the third layer L3 are layers include the first material. Thefirst material includes, for example, a metal (for example, chromium(Cr)). The first material may contain, for example, a chromium oxide.The plurality of lower layers are, for example, chromium-containingfilms. The first material may include, for example, carbon. Theplurality of lower layers may be carbon films. Hereinafter, descriptionwill be provided assuming that the first material includes chromium, butas described above, for example, other embodiments that do not includechromium may be implemented.

The plurality of upper layers contain a second material. For example,the first upper layer U1, the second upper layer U2, the third upperlayer U3, and the fourth upper layer U4 are layers including the secondmaterial. The second material includes, for example, a silicon oxide.The second material includes, for example, quartz.

The respective thicknesses of the plurality of lower layers(chromium-containing layers) are substantially the same as each other.The thickness of each of the plurality of lower layers is, for example,equal to or greater than about 5 nanometers (nm) and equal to or lessthan about 50 nm.

The respective thicknesses of the plurality of upper layers (forexample, silicon oxide layers) are substantially the same as each other.For example, the thickness of each of the plurality of upper layers isthicker than the thickness of any of the plurality of lower layers. Forexample, the thickness of each of the plurality of upper layers is about5 or more times and about 50 or less times the thickness of any of theplurality of lower layers. The thickness of each of the plurality ofupper layers is, for example, equal to or greater than about 100 nm andequal to or less than about 200 nm.

A cover film Cf serving as a cover layer, described in detail below, isprovided on the uppermost layer (e.g. the first upper layer U1). Thecover film Cf is a film including a third material (for example,chromium). In one or more embodiments the third material may be the sameas the first material. A cover layer resist film Rcf (e.g. a patternedcover layer resist film) is provided on the cover film Cf and a firstenergy ray ER1 is radiated. The first energy ray ER1 is, for example, anelectron ray. For example, electron beam drawing is performed.Alternatively, laser drawing may be performed. Thereafter, a portion ofthe cover layer resist film Rcf is removed. A resist pattern is formedfrom the cover layer resist film Rcf.

As illustrated in FIG. 1B, the cover film Cf is processed using theformed resist pattern as a mask. For example, when the cover film Cfcontains chromium, dry etching can be performed using a chlorine-basedgas and a gas mixture containing oxygen. Thus, the chromium-containingfilm is removed. The silicon oxide remains.

Thus, a plurality of cover layers (such as a first cover layer C1, asecond cover layer C2, and a third cover layer C3) are formed. The coverlayers are provided on the uppermost layer (e.g. the first upper layerU1). The plurality of cover layers contain the third material. The thirdmaterial is different from the second material. The third material maybe the same as the first material. For example, the third materialincludes chromium. The third material may include, for example, chromiumoxide. The plurality of cover layers may be provided on the stacked body12, or may constitute a portion of the stacked body 12.

The first cover layer C1 is provided on a first cover region R1 of thefirst upper layer U1. The second cover layer C2 is provided on a secondcover region R2 of the first upper layer U1. The third cover layer C3 isprovided on a third cover region R3 of the first upper layer U1. Thesecond cover layer C2 is located between the first cover layer C1 andthe third cover layer C3.

The plurality of cover layers may provide for high precision drawing.Therefore, location precision in the plurality of cover layers is high.

In this example, the widths of the plurality of cover layers aresubstantially the same. Intervals between the plurality of cover layersare substantially the same. For example, the plurality of cover layerswith a substantially same width are provided at a substantially equalpitch.

For example, the width of each of the plurality of cover layers is alength in a first direction (e.g. a horizontal direction as shown in theexample embodiments depicted in FIG. 1B) from the first cover layer C1to the second cover layer C2. The width of the second cover layer C2 (asecond length Lx2 of the second cover layer C2 in the first direction)is substantially the same as the width of the first cover layer C1 (afirst length Lx1 of the first cover layer C1 in the first direction).For example, the second length Lx2 is 0.9 or more times and 1.1 or lesstimes the first length Lx1. The width of the third cover layer C3 (athird length Lx3 of the third cover layer C3 in the first direction) issubstantially the same as the first length Lx1. For example, the thirdlength Lx3 is 0.9 or more times and 1.1 or less times the first lengthLx1.

For example, a distance (a first distance D1) between the first coverlayer C1 and the second cover layer C2 in the first direction issubstantially the same as a distance (a second distance D2) between thesecond cover layer C2 and the third cover layer C3 in the firstdirection. For example, the first distance D1 is 0.9 or more times and1.1 or less times the second distance D2.

As illustrated in FIG. 1C, a first resist film Rf1 is formed on theplurality of cover layers. For example, a material serving as the firstresist film Rf1 is applied. Thus, the first resist film Rf1 is formed.

As illustrated in FIG. 1D, a second energy ray ER2 is radiated to thefirst resist film Rf1. The radiation of the second energy ray ER2 is,for example, laser radiation. In this example, the first resist film Rf1is a positive resist film.

As illustrated in FIG. 1E, development is performed. A portion to whichthe second energy ray ER2 is radiated is removed. Thus, a first resistlayer RL1 is formed. The first resist layer RL1 covers at least aportion of the first cover layer C1 and the cover layers C2 and C3.

In some implementations, a maximum acceptable error of the location ofan end portion of the first resist layer RL1 corresponds to the width(the first length Lx1) of the first cover layer C1 (e.g. in someimplementations the end portion should be located on the first coverlayer C1). Therefore, precision (for example, location precision) may below in the radiation of the second energy ray ER2, or a margin of adevelopment region of the first resist film Rf1 can be in a broad range.

As illustrated in FIG. 1F, a portion of the first upper layer U1 isremoved using the first cover layer C1 and the first resist layer RL1 asa mask. That is, the first upper layer U1 (for example, a silicon oxide)is etched. The first material is etched. For example, dry etching isperformed using a gas such as tetrafluoromethane (CF₄). The siliconoxide film is removed. Chromium remains. Etching of the second materialas described below can also be performed through a same or similarprocess.

Thus, a portion of the first lower layer L1 is exposed. In this etching,the first lower layer L1 functions as an etching stopper. Therefore, itis possible to forma step with a highly precise specified heightcorresponding to the thickness of the first upper layer U1.

In the manufacturing method, an end portion of the mask may correspondto and end portion of the first cover layer C1 (e.g. as the mask mayinclude both the first resist layer RL1 and the first cover layer C1) inthe etching process illustrated in FIG. 1F. As described above, in theforming of the plurality of cover layers (the first cover layer C1 andthe like), the first energy ray ER1 is used. The location precision inthe radiation of the first energy ray ER1 is high. On the other hand,the second energy ray ER2 is used to pattern the first resist layer RL1.As illustrated in FIG. 1E, at least a portion of the first cover layerC1 is exposed from an end of the first resist layer RL1. This canprovide for the first cover layer C1 functioning as a mask, andtherefore, the precision of the first resist layer RL1 may be low. Thelocation precision of the second energy ray ER2 may be low.

In embodiments according to the first aspect, when the locationprecision of the first energy ray ER1 is high, the location precision ofthe second energy ray ER2 may be low. With this method, a high locationprecision can be obtained in the first upper layer U1 even whenimplementing a relatively less imprecise second energy ray ER2.

In this way, in the manufacturing method according to the first aspect,the structure 10 including the first substrate 11 and the stacked body12 is prepared. The stacked body 12 is provided on the first substrate11. The stacked body 12 includes the first lower layer L1 including thefirst material, the first upper layer U1 including the second material,and the first cover layer C1 including the third material. The secondmaterial is different from the first material. The third material isdifferent from the second material. The first upper layer U1 is providedon the first lower layer L1. The first cover layer C1 is provided on aportion (the first cover region R1) of the first upper layer U1 (seeFIG. 1B).

In the manufacturing method according to the first aspect, the firstresist layer RL1 is formed on at least a portion of the first coverlayer C1 and at least a portion of a region other than the first coverregion R1 of the first upper layer U1 (see FIG. 1E).

In some embodiments of the manufacturing method according to the firstaspect, a portion of the first upper layer U1 is removed using the firstcover layer C1 and the first resist layer RL1 as a mask to expose aportion of the first lower layer L1 (see FIG. 10F).

Through the process, a step having a highly precise specified height canbe formed. It is thus possible to provide the template manufacturingmethod capable of improved precision. As described above, the locationprecision may be low in the radiation of the second energy ray ER2.Therefore, simple, inexpensive, and/or efficient manufacturing equipmentcan be implemented. This, the step structure can be formed with a highthroughput, and a template can be manufactured with high productivity.

In embodiments according to the first aspect, the following process maybe further performed. As described above, in some embodiments, thestacked body 12 further includes the second lower layer L2 including thefirst material, the second upper layer U2 including the second material,and the second cover layer C2 including the third material. The secondlower layer L2 is provided between the first lower layer L1 and thefirst substrate 11. The second upper layer U2 is provided between thesecond lower layer L2 and the first lower layer L1. The second coverlayer C2 is provided on the second cover region R2 of the first upperlayer U1 (see FIG. 1B).

As described with reference to FIG. 1F, a portion of the first lowerlayer L1 is exposed. Thereafter, as illustrated in FIG. 2A, the firstresist layer RL1 is processed to expose the first cover layer C1. Forexample, the first resist layer RL1 is subjected to slimming. Forexample, the slimming is performed through an oxygen asher process. Inslimming described below, for example, an oxygen asher process is alsoperformed.

As illustrated in FIG. 2B, the exposed first cover layer C1 and theexposed portion of the first lower layer L1 are removed. For example,the first material and the third material (e.g. which may both includechromium) are etched. For example, dry etching is performed using achlorine-based gas and a gas mixture containing oxygen. Etching of thefirst and third materials to be described below can also be performedthrough the same process.

Thus, another portion of the first upper layer U1 and a portion of thesecond upper layer U2 are exposed.

As illustrated in FIG. 2C, the first resist layer RL1 is processed. Forexample, the first resist layer RL1 is subjected to slimming. Forexample, an end portion of the first resist layer RL1 is retreated (e.g.away from the exposed portion of the first upper layer U1) through anoxygen asking process. Thus, a portion of the second cover layer C2 isexposed. For example, an end portion of the second cover layer C2 isexposed.

As illustrated in FIG. 2D, the exposed portion of the first upper layerU1 and the exposed portion of the second upper layer U2 are removedusing the second cover layer C2 and the first resist layer RL1 as amask. For example, the second material (for example, a silicon oxide) isetched. The lower layers (e.g. the first lower layer L1 and the secondlower layer L2) including the first material may function as an etchingstopper. Another portion of the first lower layer L1 and a portion ofthe second lower layer L2 are exposed through the etching.

Through this process, a step structure that includes two steps can beformed, as shown in FIG. 2F.

In the two-step structure, the height of the steps are determined by thethickness of the plurality of upper layers and the plurality of lowerlayers. Therefore, it is possible to obtain one or more stepsrespectively having a highly precise specified height.

In the two-step structure, a precision of a width of the respectivesteps (the width of a top, exposed surface of the respective steps) isdetermined by a precision of the plurality of cover layers (e.g. thefirst cover layer C1 and the second cover layer C2). As described above,in the forming of the plurality of cover layers, the first energy rayER1 is radiated with high precision. In some implementations, in theslimming of the first resist layer RL1 described with reference to FIG.2A, an acceptable maximum error of the width of the steps corresponds tothe width (the second length) of the second cover layer C2. Thus, forexample, the precision of the slimming may be low. Therefore, simple,inexpensive, and/or efficient manufacturing equipment can beimplemented. The step structure can be formed with a high throughput. Atemplate can be manufactured with high productivity.

In this way, in some embodiments according to the first aspect, it ispossible to form the step structure including the plurality of stepswith high precision. Thus it is possible to readily improve precision.

A step structure with three or more steps can be obtained by repeatingat least some of the foregoing processes.

For example, as described above, the stacked body 12 further includesthe third lower layer L3 including the first material, the third upperlayer U3 including the second material, and the third cover layer C3including the third material. The third lower layer L3 is providedbetween the second lower layer L2 and the first substrate 11. The thirdupper layer U3 is provided between the third lower layer L3 and thesecond lower layer L2. The third cover layer C3 is provided on the thirdcover region R3 of the first upper layer U1 (see FIG. 1B).

As described above with reference to FIG. 2D, portion of the first lowerlayer L1 and portion of the second lower layer L2 are exposed. Asillustrated in FIG. 2E, the first resist layer RL1 is processed toexpose the second cover layer C2.

As illustrated in FIG. 2F, the exposed second cover layer C2, theexposed portion of the first lower layer L1, and the exposed portion ofthe second lower layer L2 are removed. For example, the first material(for example, chromium) is etched. Thus, a portion of the first upperlayer U1, a portion of the second upper layer U2, and a portion of thethird upper layer U3 are exposed. For example, the surface of the layerincluding the second material (for example, a silicon oxide) is exposed.

As illustrated in FIG. 3A, the first resist layer RL1 is processed toexpose a portion of the third cover layer C3. For example, the firstresist layer RL1 is subjected to slimming. Thus, an end portion of thethird cover layer C3 is exposed.

As illustrated in FIG. 3B, the exposed portion of the first upper layerU1, the exposed portion of the second upper layer U2, and the exposedportion of the third upper layer U3 are removed using the third coverlayer C3 and the first resist layer RL1 as a mask. For example, thesecond material (for example, a silicon oxide) is etched. Thus, aportion of the first lower layer L1, a portion of the second lower layerL2, and a portion of the third lower layer L3 are exposed.

As illustrated in FIG. 3C, the first resist layer RL1 is removed.Further, the exposed portions of the plurality of lower layers (thefirst lower layer L1, the second lower layer L2, and the third lowerlayer L3) are removed. For example, the first material (for example,chromium) is removed.

In this way, the three-step structure is formed. A step structure withany number of steps can be obtained by repeating at least some of theprocesses described above.

In embodiments according to the first aspect, as described above, theradiations of the energy rays used for processing may be performed withdifferent precisions. Thus, a template with high precision can bemanufactured with high productivity.

For example, as described above, some embodiments of the templatemanufacturing method according to the first aspect includes forming thefirst cover layer C1. The forming of the first cover layer C1 includesradiating the first energy ray ER1 to the cover layer resist film Rcfprovided on the cover film Cf to form the first cover layer C1. On theother hand, the forming of the first resist layer RL1 includes radiatingthe second energy ray ER2 to the first resist film Rf1 to form the firstresist layer RL1. In some embodiments according to the first aspect, thelocation precision in the radiation of the first energy ray ER1 ishigher than the location precision in the radiation of the second energyray ER2. In other words, the location precision in the radiation of thesecond energy ray ER2 may be relatively low. Thus, it is possible toobtain high precision even when a simple manufacturing apparatus isused. It is possible to obtain a high throughput. Thus a template can bemanufactured with high productivity.

Hereinafter, an example of a pattern forming method using the templateaccording to the first aspect will be described. In the pattern formingmethod, imprinting is performed using the template.

FIG. 4A through FIG. 4F are schematic sectional views showingembodiments of a pattern forming method using the template according tothe first aspect.

As illustrated in FIG. 4A, a first template 110 is prepared. The firsttemplate 110 includes the first substrate 11 and the stacked body 12. Astep structure 10 st of the first template 110 has a first surface 10 fthat defines one or more steps.

As illustrated in FIG. 4B, a resin liquid film 52 is provided on aprocessing substrate 51. The resin liquid film 52 comes into contactwith the step structure 10 st.

As illustrated in FIG. 4C, the resin liquid film 52 is substantiallysolidified. For example, when the resin liquid film 52 has aphotosetting property, and light (a third energy ray ER3) is radiated.In this case, the layers provided in the first template 110 havetransparency to the light. In other embodiments, the resin liquid film52 has a thermosetting property, and a heating treatment is performed.Thus, a solidified resin layer 52L can be obtained from the resin liquidfilm 52.

As illustrated in FIG. 4D, the first template 110 is detached from theresin layer 52L. The resin layer 52L has a stepped surface shape thatcomplements the first template 110.

As illustrated in FIG. 4E, an etching process 53 is performed. Forexample, reactive ion etching (RIE) or the like is performed.

As illustrated in FIG. 4F, the processing substrate 51 is thus shaped tocorrespond to the shape of the resin layer 52L.

For example, the processing substrate 51 includes a plurality of firstfilms and a plurality of second films that are alternately stacked. Thefirst films contain, for example, a silicon nitride. The second filmscontain, for example, a silicon oxide. One or more steps are formed inthe stacked first and second films by imprinting performed using thefirst template 110. In some embodiments, in a region of the processingsubstrate 51 that does not define any of the one or more steps, a memoryunit (a 3-dimensional memory cell) is provided in the stacked films. Forexample, one of the first and second films is removed. The other of thefirst and second films remains. A conductive material (for example,tungsten) is introduced in a space created by the removal of the one ofthe first and second films. In this way, a plurality of stackedconductive layers can be formed. The plurality of conductive layersserve as, for example, wirings (for example, word lines) for a pluralityof memory cells. The step portions serve as connection portions of theplurality of wirings. In this way, the template 110 according to theembodiment can be used to form the connection portions of the wirings ofa 3-dimensional memory.

FIG. 5A and FIG. 5B are schematic sectional views showing embodiments ofthe template according to the first aspect.

FIG. 5B shows stepped portions of the first template 110. FIG. 5A showsa state before the stepped portions are formed. FIG. 5A illustrates atemplate base member 210 used to form the first template 110.

As illustrated in FIG. 5A, the template base member 210 includes aplurality of first layers 61 and a plurality of second layers 62 thatare alternately stacked. The first layer 61 is a layer including thefirst material, described above. The second layer 62 is a layerincluding the second material, described above. The second material isdifferent from the first material. The thickness of the first layer 61is less than the thickness of the second layer 62. The first materialincludes, for example, chromium. The second material includes, forexample, a silicon oxide (for example, quartz).

The plurality of first layers 61 correspond to, for example, theplurality of lower layers (such as the first to third lower layers L1 toL3) described above. The plurality of second layers 62 correspond to,for example, the plurality of upper layers (such as the first to fourthupper layers U1 to U4) described above.

One of the plurality of first layers 61 may correspond to the cover filmCf described above. Alternatively, layers including the third material(described above) may be provided on the uppermost layer (the uppermostsecond layer 62) and these layers may serve as the plurality of coverlayers (the cover film Cf).

By using the template base member 210, it is possible to form a templatein accordance with the above-described manufacturing method.

As illustrated in FIG. 5B, the first template 110 includes the stackedbody 12. The stacked body 12 includes a plurality of stacked films SF.Each of the plurality of stacked films SF includes a lower layer LLincluding the first material and an upper layer UL including the secondmaterial different from the first material. One of the lower layers LLis, for example, the first lower layer L1. One of the upper layers ULis, for example, the first upper layer U1. In each stacked film SF, theupper layer UL is provided on the lower layer LL. The plurality ofstacked films SF can define one or more steps of the first template 110.

In the plurality of stacked films SF, the respective thicknesses of thelower layers LL are substantially the same as each other. In theplurality of stacked films SF, the respective thicknesses of the upperlayers UL are substantially the same as each other.

The first template 110 includes the step structure 10 st that has afirst surface 10 f. For the step structure 10 st, the respective heightsof the steps of the step structure 10 st defined by the plurality ofstacked films SF are substantially the same as each other. For the stepstructure 10 st, the widths of exposed top surfaces (“terrace” surfaces)of the steps defined by the plurality of stacked films SF aresubstantially the same as each other. The width of each terrace surfacecorresponds to, for example, a pitch of a plurality of cover layers usedin manufacture of the first template 110.

Second Aspect

Embodiments according to the second aspect relate to a templatemanufacturing method that uses a template according to the first aspect.For example, the first template 110 serving as a reference is formedaccording to the first embodiment. The first template 110 is, forexample, a master template. According to some embodiments of the secondaspect, a second template is manufactured using the first template 110.For example, a pattern for a semiconductor device or the like may beformed using the second template.

FIG. 6A through 6F are schematic sectional views showing embodiments ofa method of manufacturing a template according to the second aspect.

As illustrated in FIG. 6A, the first template 110 is prepared orprovided. The first template 110 includes a plurality of stacked filmsSF (see FIG. 5B). Each of the plurality of stacked films SF includes alower layer LL including a first material and an upper layer ULincluding a second material different from the first material. The firsttemplate 110 includes a first surface 10 f. A step structure 10 st ofthe first template 110 has a first surface 10 f that defines one or moresteps defined by the plurality of stacked films SF.

As illustrated in FIG. 6B, a resin liquid serving as a resin liquid film52 is applied onto the first surface 10 f of the step structure 10 st.The resin liquid can serve as, for example, a resist.

As illustrated in FIG. 6C, a second substrate 21 is placed on the resinliquid film 52. The second substrate 21 is, for example, a silicon oxidesubstrate (for example, a quartz substrate). The resin liquid film 52 isprovided between the first surface 10 f and the second substrate 21.

The resin liquid film 52 is substantially solidified to form a resinlayer 52L in a state in which the resin liquid film 52 provided betweenthe first surface 10 f and the second substrate 21 comes into contactwith the first surface 10 f. For example, an ultraviolet ray is radiatedto the resin liquid film 52. The ultraviolet ray may be transmittedthrough the second substrate 21 (quartz substrate).

Thus, as illustrated in FIG. 6D, the resin liquid film 52 is solidifiedto obtain the resin layer 52L. The surface of the resin layer 52L has ashape corresponding to a shape of the first surface 10 f of the stepstructure 10 st.

As illustrated in FIG. 6E, the second substrate 21 is processed usingthe resin layer 52L as a mask. For example, the silicon oxide material(for example, quartz) is etched.

Thus, as illustrated in FIG. 6F, a shape corresponding to the firstsurface 10 f of the step structure 10 st is defined by the secondsubstrate 21. Thus, a second template 120 can be obtained. The secondsubstrate 21 has a second surface shape 20C to which a shape of the stepstructure 10 st corresponds.

In some embodiments, a shape of the second surface shape 20C may be areverse of the shape of the step structure 10 st of the first template110 (e.g. depressions of the step structure 10 st may correspond toprotrusions of the second surface shape 20C, and protrusions of the stepstructure 10 st may correspond to depressions of the second surfaceshape 20C).

Further, a third template may be manufactured from the second template120 in accordance with the same method. The third template may have asimilar or same shape as the step structure 10 st of the first template110.

In this way, another template can be formed from the first template 110of the master template.

In a 3-dimensional memory, steps may thus be provided in writingconnection portions. The steps may be formed by, for example,nano-imprinting.

In some embodiments described herein, a plurality of pairs of stackedstructures are provided on the substrate. The stacked structures containa plurality of layers including different materials. A first materialincludes, for example, a metal or carbon. A second material is differentfrom the first material. The second material is, for example, siliconoxide (for example, quartz). For example, a plurality of layers (coverlayers) including a material different from the second material (whichmay be, for example, the same as or similar to the first material) areformed on the surface of the substrate. The plurality of layers have apredetermined width, and may be spaced from each other at apredetermined interval.

In some embodiments described herein, a first process and a secondprocess may be performed. In the first process, a portion of a surfaceof the substrate is covered with a resist (a first resist layer RL1)that exposes a portion of the layer including the second material. Then,the layer of the second material is etched using the resist and thelayer on the surface as a mask. In the second process, the layerincluding the first material is etched altering a region covered withthe resist. The second step is repeated a plurality of times. Thus, atemplate that has a plurality of steps is prepared.

For example, the second process includes performing an etching processon the layer including the first material after performing an ashingprocess on the resist to contract the resist and changing a position ofan end portion of the resist.

For example, the second process includes performing the ashing processon the resist to contract the resist. The second process may includeforming an additional resist after removing the resist. The forming ofthe additional resist includes performing an exposure process and adevelopment process on a material of which the additional resist ismade. The exposure process includes, for example, at least one of laserradiation and electron ray radiation.

For example, the second process includes performing the asking processon the resist to contract the resist. The second process may includeforming the additional resist after removing the resist. The forming ofthe additional resist may include, for example, performing ink jetapplication of a resist liquid and solidifying the resist liquid byradiation of light (for example, ultraviolet ray).

In some embodiments described herein, a step is formed by performing acycle of slimming→chromium etching→slimming→silicon oxide etching once.Thereafter, this process is repeated. Finally, the chromium film ispeeled off. Thus, it is possible to obtain the template with the stepshape.

The number of repetitions can be repeated with a same resist. When theresist is thinned so that the resist is resistant to the chromiumetching or the silicon oxide etching, the resist may be peeled off.Then, another resist may be formed and the process can resume from analignment drawing stage. In a process of fabricating multiple steps, theprocess can be performed with pattern precision corresponding to that ofa first drawing.

According to some embodiments described herein, for example, a templatedefining a step shape can be prepared at lower cost and with a higherthroughput than in some comparative alignment drawing methods. First,drawing is performed with high precision. A precision of a width of astep to be formed corresponds to the first pattern forming precision. Aprecision of a height of the step corresponds to the precision of thethickness of the layer. Thus, strict etching precision is unnecessary.Thus, a step template can be readily formed with high quality.

In some embodiments described herein, a stage of manufacture includingchanging a coverage of the resist can be readily performed. For example,oxygen asking can be performed under time control. Thus, an end portionof the resist can readily be moved (e.g. contracted) to an intendedposition. A dry etching process can be performed as in some chromiumetching or silicon oxide etching processes. For example, the step can beformed by repeating an etching process using oxygen, chlorine, orfluorine.

In some embodiments described herein, recovery to a start of a series ofsequences can be performed after the resist is consumed and is resistantto etching.

According to some embodiments described herein, it is possible toprovide the template manufacturing method and the template base membercapable of improved precision.

In the present specification, “vertical” and “parallel” are not strictlyvertical and strictly parallel, but also include, for example,variations or the like in the manufacturing steps, and may besubstantially vertical and substantially parallel.

The embodiments of the disclosure have been described above with respectto specific examples. However, the embodiments of the disclosure are notlimited to the specific examples. For example, specific configurationsof elements such as the lower layers, the upper layers, and the coverlayers provided in the template can be appropriately selected by thoseskilled in the art to implement embodiments of the disclosure, and areincluded in the scope of the disclosure as long as at least some of theadvantages of the embodiments described herein are provided for.

Components described herein may be combined as appropriate, providedsuch combination does not deviate from the merits of the presentdisclosure.

In addition, all the template manufacturing methods and template basemembers can be appropriately modified in design by those skilled in theart, provided such modification does not deviate from the merits of thepresent disclosure.

As used herein, the terms “about” and “substantially” are used todescribe and account for small variations. When used in conjunction withan event or circumstance, the terms “about” and “substantially” canrefer to instances in which the event or circumstance occurs preciselyas well as instances in which the event or circumstance occurs to aclose approximation. For example, when used in conjunction with anumerical value, the terms “about” and “substantially” can refer to arange of variation less than or equal to ±10% of that numerical value,such as less than or equal to ±5%, less than or equal to ±4%, less thanor equal to ±3%, less than or equal to ±2%, less than or equal to ±1%,less than or equal to ±0.5%, less than or equal to ±0.1%, or less thanor equal to ±0.05%.

As used herein, the singular terms “a,” “an,” and “the” may includeplural referents unless the context clearly dictates otherwise. In thedescription of some embodiments, a component provided “on,” “above,” or“over” another component can encompass cases where the former componentis directly on (e.g., in physical contact with) the latter component, aswell as cases where one or more intervening components are locatedbetween the former component and the latter component.

In addition, various modifications and corrections can be made by thoseskilled in the art, and such modifications and corrections are withinthe scope of the present disclosure.

While certain embodiments have been described herein, these embodimentshave been presented by way of example only, and are not intended tolimit the scope of the present disclosure. Indeed, the embodimentsdescribed herein may be embodied or combined in a variety of otherforms; furthermore, various omissions, substitutions and changes in theform of the embodiments described herein may be made without departingfrom the spirit of the present disclosure. The accompanying claims andtheir equivalents are intended to cover such forms or modifications aswould fall within the scope and spirit of the present disclosure.

What is claimed is:
 1. A template manufacturing method comprising:providing a first template, on a first substrate, that comprises aplurality of stacked films, each of the plurality of stacked filmscomprising a lower layer comprising a first material and an upper layercomprising a second material different from the first material, a firstsurface of the first template comprising a step structure in which oneor more steps are defined by the plurality of stacked films; patterninga resin layer to form a mask, wherein the patterning the resin layercomprises disposing a resin liquid film between the first template and asecond substrate; solidifying the resin liquid film while the firstsurface of the first template is in contact with the resin liquid filmto pattern the resin layer defining a resin layer surface shape thatcorresponds to a shape of the step structure, wherein the solidifyingthe resin liquid film comprises radiating an ultraviolet ray to theresin liquid film through the second substrate; and forming a secondtemplate, using the mask arranged on a surface of the second substrate.2. The template manufacturing method according to claim 1, wherein thefirst material comprises a metal comprising chromium.
 3. The templatemanufacturing method according to claim 2, wherein the first materialcomprises a chromium oxide.
 4. The template manufacturing methodaccording to claim 3, wherein the second material comprises a siliconoxide or quartz.
 5. The template manufacturing method according to claim1, wherein the first material comprises carbon.